Pipe-threading mechanism



April 26, 1927. 1,626,251

H. D. PENNINGTON PIPE THREADING MECHANISM Filed March 1923 V 4 Sheets-Sheet l v 1,626,251 Ap 1927' H. D. PENNINGTON PIPE THREADING MECHANI SM Filed March 1 1925 v 4 Sheets-Sheet 2 1927. Apnl H. D. PENNINGTON PIPE THREADING MECHANISM 4 4 Sheets-Sheet 3 Filed March 1923 April 26,1927. I 1,626,251

Y H. D. PENNINGTON PI PE THREADING MECHANI SM Filed March 16. 1923 4 Sheets-Sheet 4 fly. 4

fiz Z@%LVENTIOR v M /M Patented Apr. 26, 1927;

UNITED STATES HARLEY D. PENNING'ION, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO UNITED ENGINEERING AND FOUNDRY COMPANY, OF

CORPORATION OF PENNSYLVANIA.

PITTSBURGH, PENNSYLVANIA, A

PIPE-THREADING MECHANISM.

Application filed March 13, 1923. Serial No. 624,759;

The present invention relates broadly to threading mechanism, and more particularly to pipe-threading mechanism.

An objection to pipe-threading mechanisms as heretofore constructed has been that the threading die was mounted upon a slide adapted to reciprocate in one axial direction only. It often occurs that a pipe to be threaded is not perfectly straight so that the end in engagement with the threading die tends to move in an orbital path. It is therefore desirable to mount the threading die to permit such movement of the end of the pipe when in engagement with. the die. In accordance with the present invention the threading (lie is mounted upon a head which is arranged for reciprocation in two axial directions at right angles to each other so that the die is enabled to move in an orbital path without putting any strain upon the pipe or the threading mechanism. Moreover this construction facilitates the centering of the die with respect to the pipe and also insures the cutting of a true thread.

Another objection to pipe-threading mechanisms as heretoforeconstructed has been that chips cut from the pipe in threading the same fell upon the bed of the machine and, being ground between the surfaces of the sliding carriage and bed, caused the scoring of said surfaces. By the present invention this objection is overcome by mounting the carriage upon rollers and providing the bed of the machine with guards arranged to shield the tracks engaged by the rollers. The mounting of the carriage upon rollers also reduces friction between the carriage and bed thereby relieving the threads on the pipe and the threading die itself from much of the load imposed thereon due to the pull or drag of the carriage during the threading operation.

Another feature of the invention is the provision of a reamer comprising a reamer blade having a cutting edge on each of its opposite ends and a support therefor to which said blade is detachably secured whereby the position of the blade may be reversed end for end or a different blade substituted therefor.

In the accompanying drawings there is shown, for purposes of illustration only, one embodiment of the present invention, it being understood that the drawings do not define the limits of the invention, as changes may be made in the construction and operation therein disclosed without departing from the spirit of the invention or scope of my broader claims.

In the drawings:

Figure 1 is a side elevation of a pipethreading mechanism constructed in accordance with my invention;

Figure 2 is a plan view of the reciprocating carriage and the parts carried thereby;

Figure 3 is a view partly in longitudinal section and partly in elevation of the parts illustrated in Figure 2;

Figure 4- is an end elevation, partly in section, of the construction illustrated in Figure 2, and

Figure 5 is a detail View of the reamer and the detent actuated thereby.

Referring to the drawings, A designates the bed of the machine, at one end of which is mounted a housing B in which is contained the means for gripping and rotating the pipe and upon the bed A is also mounted a reciprocable carriage C which carries the threading die.

Any suitable means for rotating the pipe may be provided, that herein shown comprising a barrel 2 suitably journaled for rotation in the housing B and adapted to receive and guide the pipe to be threaded. Mounted for reciprocation uponthe barrel 2 and for rotation therewith is a collar 3 having at one end thereof a cam member 4 adapted to engage rollers 5 at one end of levers 6. The levers 6 may be pivoted intermediate their ends .to the barrel 2. The levers 6 operatively engage adjustable sliding chucks 7, these chucks being arranged to grip the pipe when the parts are in the position illustrated in Figure 1. The collar 3 mav be actuated by fluid-pressure means including a cylinder 8 and piston 9, the latter being operatively connected to the collar by a piston rod 10 and lever 11. For controlling the operation of the fluid-pressure actuating means, a suitable valve (not shown) may be provided. Fixed to the barrel 2 is a relatively large gear 2' which is operatively connected through a suitable gear train with a driving motor (not shown).

The threading die is made in two' parts 12 and 18 mounted upon a die-head 14, each art being pivoted at its lower end upon the olt carried by said head. Each of the parts 12 and 13 is provided at its upper end with a pin 16 engaging in a cam slot 17 in the cam disc .18. It will be apparent that rotation of the cam disc 18 in one direction will cause the parts 12 and 13 to swing outwardly about the pivot bolt 15 to open the die and that movement of said disc in the opposite direction will cause said parts to swing inwardly about said pivot bolt to 7 close the die.

A connecting rod 19 is pivotally mounted at one end upon a pin 20 projecting upwardly from the cam disc 18 and its opposite end is pivotally connected to one end of a lever 21. The lever 21, at its opposite end, is fixed to the upper end of a vertical shaft 22 journaled in the carriage C. Fixed to the shaft 22 intermediate the ends of the latter is a cam 23 having a shoulder 24. The shoulder 24 is normally engaged by a shoulder on the end of a bell-crank lever 25. The bell-crank lever 25 is pivoted" at 26 upon the end of a bracket 27 carried b the carriage C. A bifurcated bell-crank lever '28 is also pivoted at one end upon the pivot 26, the arm 29 of said lever 28 being arranged to straddle the arm 30 of the lever 25. A removable pin 31 passess through the angle of the lever 28 and through the end of the arm 30 to rigidly secure the arms 29 and 30 together. Mounted in-the free end of the lever28 is an adjustable abutment in the formof a screw 32, for a purpose to be hereinafter desclosed.

A spring 33 is connected at one end to the bracket 27 and at its opposite end to the lever 25, this spring tending. to normally maintain the shoulder on the lever 25 in engagement with the shoulder24 on the cam 23. A spring 34 is connected at one end to the lever 21 and at its opposite end to the carriage-C, this spring tending to move the lever 21 in a direction to open the threading I die.

The die-head 14 has a cylindrical bore 35 to receive the end of a-pipe, and mounted in the carriage C is areamer holder 36 having a bore in axial alinement with the bore 35. The reamer comprises a fiat, substantially square, blade 37 of a width corresponding substantially to the diameter of the pipe to be threaded. The blade 37 is cut away at each of its four corners as'indicated at 38, the two cut-away corners on either end of the blade 37 being adapted to engage the end of a pipe to ream the same and remove any burr therefrom. The blade 37 projects into a slot in the end of a stem 39 and is detachably secured therein by-means of bolts 40,

-whereby said blade 37 may have its position portion 41 which is rectangular in cross section and slidably engaged in the-bore of the holder 36. The adjustable abutment 32 carried by the lever 28 normally engages the free end of the portion 41.

The carriage C is mounted for reciprocation on the bed A and for moving the same manually thereon a rod 42 is pivotally connected at one end to a hand-lever 43 and at its opposite end is provided with a bifurcated portion in the form of an inverted U straddling a pin 42 projecting from the carriage C. Fixed upon the bed A is an abutment 44 adapted to engage an arm 45 fixed to the lower end of the vertical shaft 22.

The operation of the parts so far described is substantially as follows: Assuming that a pipe is in the position shown in Figure 3, it will be seen that the end of the rotating pipe is engaged by the reamer blade 37 which is adapted to ream the same and remove any burr therefrom. The rotation of the .pipe in the die draws the car riage C towards the housing B and, there'- fore, as soon as the reamer blade 37 engages the end of the pipe, the reamer will be held stationary by its engagement with the pipe while the carriage continues to move. Since the pivot 26 of'the combined levers 25 and 28 is moving with the carriage while the abutment 32 is in engagement withthe end of the portion 41 of the reamer, the shoulder on the end of the lever 25 will be moved out of engagement with the shoulder 24 on the cam 23 in the continued movement of the carriage. As soon as this occurs, the spring 34 will move the lever 21. in a clockwise direction and thereby' open the threading die through the connecting rod 19, cam disc 18, pins 16 and slots 17. It will be readily seen, that'by proper adjustment of the abutment 32 carried by the lever 28, the moment at which the threadingdie will be opened can .be predetermined. In other words, this construction provides means for predetermining the length of the screw thread lever 21, connecting rod 19, cam disc 18, pins 16 and slots 17, as will be obvious. Moreover, when'the lever 25.snaps into engagement with the shoulder 24 on the cam 23, the abutment 32 causes the reamer to slide forwardly in the holder 36 into proper posi- .tion to engage the end of the next pipe to' be threaded. Having caused the automatic closing of the die in the manner described, the operative will now take another pipe from the pipe rack and push the same through the barrel 2 until the end of the pipe to bethreaded is adjacent to, but not in engagement with, the threading die. He will then render the pipe rotating means operative and thereafter actuate the hand lever 43 to move the carriage C towards the housing B to bring the threading die into engagement with end of the rotating pipe. Since the pipe rotating means holds the pipe against axial movement, the threading operation causes the carriage C to move towards the housing B until the end of the pipe .engages the reamer blade 37 whereupon. the die is automatically opened, as hereinbefore described.

The die-head 14 is slidably mounted in a cross-slide member 46 for reciprocation in a horizontal direction at right angles to the axis of the bore 35. The cross-slide member 46 is slidabl mounted in a vertical slide member 47 or reciprocation in a vertical direction. Bolted to the upper edge face of the cross-slide member 46 adjacent the opposite ends thereof are a pair of spring clips 48. Each of the spring clips 48 has a slotted free end portion engaging the upper end of a coil spring 49. Each coil spring 49 surrounds a vertical bolt 50 carried by the carriage C and having on its lower threaded end portion a nut 51 held against rotation in the carriage C. Each bolt 50 has a faceted head 52 on its opposite end and hinged to the carriage C adjacent each of the heads 52 is a lock clip 53 having a bifurcated end portion adapted to engage diametrically opposite faces of thehead 52 and thereby prevent turning of the bolt. When it is desired to vary the tension of the springs 49, the lock'clips 53 may be swung out of engagement with the heads 52 and the bolts 50 rotated until the desired tension of the springs is obtained. The springs 49 and the elements operativelyv connecting the springs to the cross-slide member 46 constitute balance means for balancing the weight of the die-head 14 and the parts carried thereby.

It sometimes happens that a pipe to be threaded has a flattened portion. Suitable roundingmeans may be provided for engaging the fiattened ortion and bringing the same into true cy indrical form. Such rounding means may comprise a rounding -die 54 made in two parts and interpose between the die-head 14 and the reamer holder 36. The lower half of the rounding die is fixedly mounted in the carriage but the upper half thereof is mounted for vertical sliding movement and the position of this upper half may be adjusted bymeans of a vertical screw 55 extending through suitable openings in a portion of the carriage C and engaging a nut 56 held against rotation in said carriage. The upper end of said screw may be provided with a suitable handle 57 and the lowerend thereof may have a head 58 engaging in a suitable groove in the upper face of the upper half of the die 54. The construction is such as to permit the vertical adjustment of the upper half of the die 54 while permitting said die to be readily assembled with said actuating screw 55.

It sometimes occurs that the end of the pipe to'be threaded is not square or is mutilated and it is desirable to trim off such end portion preliminary to the threading operation. For this purpose a suitable knife 59 may be provided. This knife is mounted in a suitable knife holder 60'slidably mounted in the carriage C. For moving the knife 59 to and from operative position, a screw 61 is provided. The screw 61 has a'threaded end portion engaging a nut 62 held against rotation in the carriage C. Said screw also has a portion journaled in a portion of the knife holder 60 and for rotating the screw a suitable handle 63 is provided.

It will be apparent that when it is desired to utilize either the rounding die 54 or the knife 59, it will be necessary to remove the reamer from the machine and to move the reamer holder 36 out of the path of the pipe to be operated upon. In order to permit the removal of the reamer, the pin 31 connecting the arm 29 of lever 28 to arm 30 of lever 25 must be removed. When this is done, the lever 28 can be swung around on the pivot 26 out of the path of the reamer and the latter can be withdrawn from the holder 36, it being noted, by reference to Figure'3, that the holder 36 is provided with suitable slots 64 forming extensions of its bore, which slots in conjunction with the bore permit the removal of the reamer mem- \been removed, said holder can be slid to the right (Figure 4:) until it clears the path of the pipe. The pipe .can then be pushed through the die-head 14 and rounding die 54 into proper position for either the rounding operation or the trimming operation. Preparatory to the trimming operation, the

rounding die is adjusted to engage the pipe to hold the same in proper position during said operation.

The bed A is provided with suitable parallel tracks 65 and the carriage C is supported ;for reciprocation on the bed by means of rollers 66 which engage said tracks and are journaled upon fixed pins 67 carried by the carriage, suitable roller bearings 68 being interposed between the pins and rollers. For preventing fragments of metal from fallin upon the tracks 65, each track is provide with a suitable shield. Such shield com prises a vertical flange 69 depending from the carriage C and arranged above and at the outer'side' of the track 65. The flanges 69 at the opposite sides of the carriage are formed with integral horizontal bearing portions 69' in which the rollers 66 are journaled upon the fixed pins 67 hereinbefore referrcd to. Fixed to the bed A adjacent each track 65 is a member 70 comprising a vertical flange 71 extending above and at the inner side of the track 65 and a substantially horizontal flange 7 2 integral with said flange 71 and extending towards the flange 69 at the outer side of said track. It will be noted from Figure 4 that the flange 72 projects outwardly beyond the flange 65. This is of advantage in shielding the tracks or flanges 65 from chips. The members 7 O extend substantially throughout the length of the tracks 65 and are bolted or otherwise secured to the bed A with provision for vertical adjustment, and interposed between the lower edge of each member 70 and a shoulder 73 on the bed A is a thin strip of metal 74. The vertical flange 71 of each member 70 is formed adjacent its upper edge with a downwardly facing shoulder 75 parallel to the corresponding track 65, which shoulder is slidably engaged by the upper edge face of the inner end portion of each bearing portion 69' formed on the corresponding flange 69. This engagement of the bearing portions 69 with the shoulders 7 5 prevents tipping of the carriage C on the bed A. The inner face of each vertical flange 71 is slidably en aged by the upper portion of the end face of each bearing portion 69 formed on the corresponding flange 69 and this engagement of the bearing portions 69 with the inner faces of the flanges 71 prevents the carriage C from shifting transversely of the bed A. It will be seen that the members 7 0 form guides for guiding the reciproeatory movements of the carriage C on the bed A and that these members inconjunction with the flanges 69 form housings which protect the tracks 65 and rollers 66, thereby eliminating the possibility of'the tracks becoming scored due to whether there is a direct sliding engagement between the carriage and tracks, as in either case unscored tracks are insured.

Secured to the lower edge of each of the flanges 69 is a rack 76, and journaled in the bed A and extendingtransversely thereof is a shaft 77 having fixed to one end thereof a suitable handle 78. The shaft 77 has fixed thereto a pair of pinions 79 meshing with the racks 7 6, one of said pinions bein shown in Figure 1. When it is desiref to utilize either the rounding die 54 or the knife 59,-the operative may move the carriage to any desired position on the bed A by actuating the handle 78, disconnecting the rod 42 from said carriage if desired.

An important advantage of the present invention arises from the mounting of the die-head whereby the threading die has provision for universal movement in a plane at right angles to the axis of the pipe being threaded.

Another advantage of the present invention arises from the provision of means for balancing the weight of the die-head and the parts carried thereby.

A further advantage of the invention arises from the mounting of the carriage upon rollers and the provision of means for shielding the tracks from falling scraps of metal, which means also serves to guide the reciprocatory movements of the carriage on the bed and revents the carriage from tipping on the ed.

Another advantage of the invention arises from the provision of a reamer having a reversible reamer blade provided with a cutting edge on each of its opposite ends.

I claim:

1. In pipe-threading mechanism, a threadfrom said carriage at t e outer sides of said tracks, flanges extending upwardly from the bed at the inner sides-of said tracks, and flanges mtegral with said upwardly extendin flanges and extending horizontall over said tracks, substantially as describe 2.In pipe-threading mechanism, a threading-die, a carriage for said die, a bed hav-.

head, a slide member supporting said die-head for free reciprocation therein in a horizontal direction, a slide member supporting said first mentioned slide member for reciprocation in a vertical direction, spring means for balancing said second-mentioned slide member, and means for adjusting the tension of said spring means to vary the balancing effect thereof, substantially as described.

4. In pipe-threading mechanism, a bed having a pair of. parallel tracks, a treading die, a carriage for said die having a plurality of anti-friction rollers in engagement with each of said tracks, a bearing portion for each of said rollers carried by said carriage, and a member supported by said bed adjacent each of said tracks and substantially co-extensive in length therewith, said member having a downwardly facing shoulder above and parallel to the corresponding track, the bearing portions of the rollers engaging the corresponding track slidably ensaid shoulder, substantially as descr1 e 5. In pipe-threading mechanism, a bed provided with tracks, a threading die, a carriage for said die mounted for reciprocation on said tracks, and means for shieldin all portions of said tracks engaged by said carriage from falling metal, said means forming an interlock between said bed and carriage to prevent tipping of said carriage on said bed, substantially as described.

In testimony whereof I have hereunto set my hand. 4

4 HARLEY D. PENN INGTON. 

